Motor vehicles, such as automobiles, include those having internal combustion engines which include an air intake manifold having a first shell and a second shell. The second shell is mounted to a portion of the engine, and the first shell is attached (such as at fixing locations on the perimeter rim of the cover) to the second shell to surround an internal manifold volume. The intake-manifold first shell has raised sides and a substantially flat top. In some conventional designs, the top of the first shell includes fixing locations for fasteners extending from the top of the first shell to the second shell of the air intake manifold and includes added ribs all to improve both pressure resistance to sudden pressurization (as from an engine backfire) and acoustical barrier properties. Multi-layered air intake manifolds having three or four shells are also known.
What is needed is an improved engine air intake manifold having a shell.